This application is based on application No.054562/2000 filed in Japan on Feb. 29, 2000, the content of which incorporated hereinto by reference.
This invention relates to an electric shaver which turns on and off with a push button switch, and in particular to an electric shaver in which the push button switch is attached in a watertight configuration.
In an electric shaver provided with a push button switch, switch operation is easier than with a slide switch because the motor can be turned on and off by simply pushing the push button switch. Further, a push button switch has the characteristic that it can be made watertight with a simple structure. This is because a push button switch can be made watertight without parts that move along the case surface as in the slide switch.
FIG. 1 is a cross section view showing the structure of a push button switch with a watertight configuration. In FIG. 1, the push button switch 1019 disposed inside the case 101 is switched on and off with the push button 1020. A switch window 101B in the case 101 is sealed in a watertight fashion with a waterproof gasket 1028 to attach the push button 1020 to the case 101 in a watertight configuration. The waterproof gasket 1028 is provided with an insertion groove 1028A for insertion of a periphery ridge 1024 provided around the periphery edge of the switch window 101B. Further, the outer periphery of the waterproof gasket 1028 is banded to tightly seal the insertion groove 1028A to the periphery ridge 1024 and completely seal the switch window 101B with the waterproof gasket 1028. The push button 1020 is disposed interior to the insertion groove 1028A of the waterproof gasket 1028. In this structure, when the push button 1020 is pushed, the waterproof gasket is distorted and the push button switch 1019 is pressed.
The watertight structure shown in FIG. 1 has the drawback that installation of the waterproof gasket is troublesome. This is because the periphery ridge is inserted into the insertion groove of the waterproof gasket and the unit is banded together in this state with a band around the outer periphery of the waterproof gasket. Further, to make this configuration more completely watertight, it is necessary to increase the height of the periphery ridge for reliable banding of the outer periphery of the waterproof gasket. Therefore, this configuration also has the drawback that the attachment region for the push button becomes thicker. Still further, since the push button is directly connected to the waterproof gasket, it is difficult to move the push button in the direction of pressing while maintaining a fixed stable position. This is because the position of push button moves in the horizontal plane when the waterproof gasket distorts.
The present invention was developed to resolve these types of problems. Thus it is a primary object of the present invention to provide an electric shaver in which the region provided with a push button can be easily assembled and the switch window opened through the case can be reliably sealed in a watertight fashion.
Further, it is another important object of the present invention to provide an electric shaver in which the region comprising the push button can be designed as a thin structure and still be sufficiently watertight, and the push button can be stroked at an accurate position in the direction it is pressed.
The above and further objects and features of the invention will more fully be apparent from the following detailed description with accompanying drawings.
The electric shaver of the present invention is provided with a push button switch inside the case, a push button to press and switch on and off the push button switch disposed in the switch window of the case, and a waterproof gasket disposed between the push button and the push button switch to seal the case switch window in a watertight configuration. Further, the electric shaver of the present invention is provided with all of the following structures.
The case switch window has a periphery ridge projecting outward from the switch window periphery edge. The waterproof gasket has an upper surface contact region for contact with the upper edge of the periphery ridge, and an inner surface contact region for contact with the inside surface of the periphery ridge. An inner ring is disposed inside the waterproof gasket inner surface contact region to tightly seal the waterproof gasket inner surface contact region with the periphery ridge. The push button is disposed inside the inner ring in a manner allowing the push button to move in the direction it is pushed.
An electric shaver with this configuration has the characteristic that assembly of the region including the push button is simple and the switch window opened through the case can reliably be made watertight. This is because the waterproof gasket is disposed at the periphery ridge provided around the periphery edge of the switch window in the case of this electric shaver. This waterproof gasket has an upper surface contact region for contact with the upper edge of the periphery ridge, an inner surface contact region for contact with the inside surface of the periphery ridge, as well as an inner ring disposed inside the inner surface contact region which tightly seals the waterproof gasket inner surface contact region with the periphery ridge. Further, the push button is disposed within the inner ring in a manner allowing it to move in the direction it is pressed. The region of this configuration of electric shaver provided with the push button can be designed as a thin structure and sufficiently watertight even though assembly is simple and the waterproof gasket is reliably disposed in a fixed position. Further, since the push button of the electric shaver of the present invention moves inside the inner ring, it is characterized by accurate position and a stroke in the direction of pressing.
In the electric shaver of the present invention, the waterproof gasket can be attached in a given location on the case by a surface cover fixed to the case. Further, the inner ring of the electric shaver of the present invention can be attached in a given location on the case by a surface cover fixed to the case.
In the electric shaver of the present invention, the inner ring can be formed as a single piece connected to a cosmetic plate fixed to the surface of the case. Preferably, light windows are provided in this cosmetic plate to shine light outside from lamps installed in the case.
The cosmetic plate of the electric shaver of the present invention can be attached in a fixed position to the case surface in a pressure-fit configuration. Further, the surface cover fixed to the case can press the outer edge of the cosmetic plate to attach the cosmetic plate to a fixed position on the case.
Finally, connection hooks can be provided on the surface cover for connection to the case of the electric shaver of the present invention. In this electric shaver, the connection hooks can be connected with the case to fix the surface cover in a given position on the case.